From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Letter from Lake & Elliot discussing brake drum performance and the metallurgical structure of Millenite.
| Identifier | ExFiles\Box 142\4\ scan0168 | |
| Date | 17th February 1936 | |
| Copy of letter From: LAKE & ELLIOT. BRAINTREE Essex. Feb.17th.1936 Messrs. Rolls-Royce Ltd. Nightingale Road Derby. Dear Sirs, We thank you for the interviews granted to Mr. Kain and Mr. Whitfield on Friday last and wish to confirm their visit. It is our experience that a plain Brake Drum with a single rib and having the disc at the back cast integral with the Drum appears to give the most satisfactory result in service. We have had only one other complaint of Millenite in Brake Drums and this also occurred upon a ribbed Drum. Regarding the internal structure of the metal, we found during our early experiments with the High Frequency Furnace that the peculiar structure recommended to you by Mr. Field occurred from time to time accidentally and could with some difficulty be produced by intention. Our interpretation of the photomicrograph is that the structure consists of a dendritic formation of large areas of Ferrite or pure Iron containing other elements, such as Silicon in solution, and areas of very fine Carbon in a condition similar to the amorphous. It is almost impossible to obtain this structure throughout a given section, and we wish to emphasize again that in every case we have found that the performance of the material in service has been exceedingly poor. (Cont'd) ENCLOSURE Nº 527 "JUSTSO" | ||